Plasticized sulfur compositions are well known in the art. These compositions can be prepared by reacting from about 1 to 50 parts by weight of a polythiol with 100 parts by weight of sulfur. A basic catalyst is usually utilized to reduce the reaction time. Hydrogen sulfide is given off during the process.
The properties of the plasticized sulfur compositions are unpredictable since they are dependent upon the temperature of the reaction, the reaction time, the amount of catalyst used, the concentration of the polythiol, the nature of the polythiol and the temperature history of the reaction mixture. As disclosed in the U.S. Pat. No. 3,434,852, to provide a material within a usable viscosity range, it is the custom to introduce viscosity improving or viscosity reducing agents into the plasticized sulfur composition.
Whenever a plasticized sulfur composition is heated, the properties of the composition change. Viscosity improvers are added to the plasticized sulfur compositions to compensate for increases in viscosity which accompany heating said plasticized compositions. The visocosity of the molten plasticized sulfur compostions can be stabilized by introducing monomercaptans along with polythiols into the reaction mixture.
Plasticized sulfur compositions and their method of preparation are disclosed in U.S. Pat. Nos. 3,434,852; 3,734,753; 3,453,126 and British Patent 1,303,832.
It is an object of the present invention to provide a method for plasticizing sulfur without the liberation of hydrogen sulfide. It is also an object of the present invention to provide plasticized sulfur compositions with reproducible properties. It is a further object of the present invention to provide a method for rapidly preparing plasticized sulfur.